174 Commits

Author SHA1 Message Date
Sjoerd Meijer
fade1bf838 Code size optimisation: don't rewrite fputs to fwrite when optimising for size
because fwrite requires more arguments and thus extra MOVs are required.

llvm-svn: 274753
2016-07-07 13:56:23 +00:00
Joerg Sonnenberger
30460c8dd2 Optimize a printf with a double procent to putchar.
llvm-svn: 268922
2016-05-09 14:36:16 +00:00
Ahmed Bougacha
fff706e40a [TLI] Unify LibFunc signature checking. NFCI.
I tried to be as close as possible to the strongest check that
existed before; cleaning these up properly is left for future work.

Differential Revision: http://reviews.llvm.org/D19469

llvm-svn: 267758
2016-04-27 19:04:35 +00:00
David Majnemer
67f60eaa89 Revert "[SimplifyLibCalls] sprintf doesn't copy null bytes"
The destination buffer that sprintf uses is restrict qualified, we do
not need to worry about derived pointers referenced via format
specifiers.

This reverts commit r267580.

llvm-svn: 267605
2016-04-26 21:04:47 +00:00
David Majnemer
5541fe7f24 [SimplifyLibCalls] sprintf doesn't copy null bytes
sprintf doesn't read or copy the terminating null byte from it's string
operands.  sprintf will append it's own after processing all of the
format specifiers.

This fixes PR27526.

llvm-svn: 267580
2016-04-26 18:16:49 +00:00
Mehdi Amini
9ff867f98c [NFC] Header cleanup
Removed some unused headers, replaced some headers with forward class declarations.

Found using simple scripts like this one:
clear && ack --cpp -l '#include "llvm/ADT/IndexedMap.h"' | xargs grep -L 'IndexedMap[<]' | xargs grep -n --color=auto 'IndexedMap'

Patch by Eugene Kosov <claprix@yandex.ru>

Differential Revision: http://reviews.llvm.org/D19219

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266595
2016-04-18 09:17:29 +00:00
David L Kreitzer
cc655b3f3d Simplify strlen to a subtraction for certain cases.
Patch by Li Huang (li1.huang@intel.com)

Differential Revision: http://reviews.llvm.org/D18230

llvm-svn: 266200
2016-04-13 14:31:06 +00:00
Davide Italiano
52a0dab957 [SimplifyLibCalls] Garbage collect dead code.
We already skip optimizations if the return value
of printf() is used, so CI->use_empty() is always
true.

Differential Revision:  http://reviews.llvm.org/D18656

llvm-svn: 265253
2016-04-03 01:46:52 +00:00
Davide Italiano
09b1f874a9 [SimplifyLibCalls] Transform printf("%s", "a") -> putchar('a').
llvm-svn: 264588
2016-03-28 15:54:01 +00:00
David Majnemer
ab6aef2bdd [SimplifyLibCalls] Only consider sinpi/cospi functions within the same function
The sinpi/cospi can be replaced with sincospi to remove unnecessary
computations.  However, we need to make sure that the calls are within
the same function!

This fixes PR26993.

llvm-svn: 263875
2016-03-19 04:53:02 +00:00
Sanjay Patel
906306d436 [LibCallSimplifier] fold memset(malloc(x), 0, x) --> calloc(1, x)
This is a step towards solving PR25892:
https://llvm.org/bugs/show_bug.cgi?id=25892

It won't handle the reported case. As noted by the 'TODO' comments in the patch, 
we need to relax the hasOneUse() constraint and also match patterns that include
memset_chk() and the llvm.memset() intrinsic in addition to memset().

Differential Revision: http://reviews.llvm.org/D16337

llvm-svn: 258816
2016-01-26 16:17:24 +00:00
Sanjay Patel
ef7cae166d move function definitions so we don't need separate declarations ; NFCI
llvm-svn: 258455
2016-01-21 23:38:43 +00:00
Sanjay Patel
ff5da390f5 [LibCallSimplifier] refactor FP function signature checks ; NFCI
Use the helper function added in r258428.

The check should really be hoisted to the caller of all of these
optimize* functions, but that's another step.

llvm-svn: 258446
2016-01-21 22:58:01 +00:00
Sanjay Patel
7c9dc49b45 avoid variable shadowing; NFC
llvm-svn: 258445
2016-01-21 22:41:16 +00:00
Sanjay Patel
4a76c00379 remove unnecessary variable; NFC
llvm-svn: 258444
2016-01-21 22:31:18 +00:00
Sanjay Patel
1087b8fb2a [LibCallSimplifier] don't get fooled by a fake fmin()
This is similar to the bug/fix:
https://llvm.org/bugs/show_bug.cgi?id=26211
http://reviews.llvm.org/rL258325

The fmin() test case reveals another bug caused by sloppy
code duplication. It will crash without this patch because
fp128 is a valid floating-point type, but we would think
that we had matched a function that used doubles.

The new helper function can be used to replace similar
checks that are used in several other places in this file.

llvm-svn: 258428
2016-01-21 20:19:54 +00:00
Sanjay Patel
9447739046 make helper functions static; NFCI
llvm-svn: 258416
2016-01-21 18:01:57 +00:00
Sanjay Patel
3635b71b45 [LibCallSimplifier] don't get fooled by a fake sqrt()
The test case will crash without this patch because the subsequent call to
hasUnsafeAlgebra() assumes that the call instruction is an FPMathOperator
(ie, returns an FP type).

This part of the function signature check was omitted for the sqrt() case, 
but seems to be in place for all other transforms.

Before:
http://reviews.llvm.org/rL257400
...we would have needlessly continued execution in optimizeSqrt(), but the
bug was harmless because we'd eventually fail some other check and return
without damage.

This should fix:
https://llvm.org/bugs/show_bug.cgi?id=26211

Differential Revision: http://reviews.llvm.org/D16198

llvm-svn: 258325
2016-01-20 17:41:14 +00:00
Sanjay Patel
73930e2b84 function names start with a lowercase letter; NFC
Note: There are no uses of these functions outside of
SimplifyLibCalls, so they could be static functions in
that file.

llvm-svn: 258172
2016-01-19 19:46:10 +00:00
Sanjay Patel
a2ab3d6165 [LibCallSimplifier] use instruction-level fast-math-flags to shrink calls
This is a continuation of adding FMF to call instructions:
http://reviews.llvm.org/rL255555

llvm-svn: 258158
2016-01-19 18:38:52 +00:00
Sanjay Patel
a46637dede [LibCallSimplifier] use instruction-level fast-math-flags to transform pow(x, [small integer]) calls
This is a continuation of adding FMF to call instructions:
http://reviews.llvm.org/rL255555

As with D15937, the intent of the patch is to preserve the current behavior of the transform
except that we use the pow call's 'fast' attribute as a trigger rather than a function-level
attribute.

The TODO comment notes a potential follow-on patch that would propagate FMF to the new
instructions.

Differential Revision: http://reviews.llvm.org/D16122

llvm-svn: 258153
2016-01-19 18:15:12 +00:00
Sanjay Patel
489a46e98d [LibCallSimplifier] use instruction-level fast-math-flags to transform pow(x, 0.5) calls
Also, propagate the FMF to the newly created sqrt() call.

llvm-svn: 257503
2016-01-12 19:06:35 +00:00
Sanjay Patel
eb6cf93f57 function names start with a lower case letter ; NFC
llvm-svn: 257496
2016-01-12 18:03:37 +00:00
Sanjay Patel
91e6a8ee15 [LibCallSimplifier] use instruction-level fast-math-flags to transform pow(exp(x)) calls
See also:
http://reviews.llvm.org/rL255555
http://reviews.llvm.org/rL256871
http://reviews.llvm.org/rL256964
http://reviews.llvm.org/rL257400
http://reviews.llvm.org/rL257404
http://reviews.llvm.org/rL257414

llvm-svn: 257491
2016-01-12 17:30:37 +00:00
Sanjay Patel
42e7daf81c [LibCallSimplifier] use instruction-level fast-math-flags to transform log calls
Also, add tests to verify that we're checking 'fast' on both calls of each transform pair,
tighten the CHECK lines, and give the tests more meaningful names.

This is a continuation of:
http://reviews.llvm.org/rL255555
http://reviews.llvm.org/rL256871
http://reviews.llvm.org/rL256964
http://reviews.llvm.org/rL257400
http://reviews.llvm.org/rL257404

llvm-svn: 257414
2016-01-11 23:31:48 +00:00
Sanjay Patel
dfd0791d6d [LibCallSimplifier] don't allow sqrt transform unless all ops are unsafe
Fix the FIXME added with:
http://reviews.llvm.org/rL257400

llvm-svn: 257404
2016-01-11 22:50:36 +00:00
Sanjay Patel
68ad8ce279 more space; NFC
llvm-svn: 257401
2016-01-11 22:35:39 +00:00
Sanjay Patel
9ac7e74796 [LibCallSimplifier] use instruction-level fast-math-flags to transform sqrt calls
This is a continuation of adding FMF to call instructions:
http://reviews.llvm.org/rL255555

The intent of the patch is to preserve the current behavior of the transform except
that we use the sqrt instruction's 'fast' attribute as a trigger rather than the
function-level attribute.

But this raises a bug noted by the new FIXME comment.

In order to do this transform:
sqrt((x * x) * y) ---> fabs(x) * sqrt(y)

...we need all of the sqrt, the first fmul, and the second fmul to be 'fast'. 
If any of those ops is strict, we should bail out.

Differential Revision: http://reviews.llvm.org/D15937

llvm-svn: 257400
2016-01-11 22:34:19 +00:00
Sanjay Patel
6307d280cd [LibCallSimplifier] less indenting; NFCI
llvm-svn: 256973
2016-01-06 20:52:21 +00:00
Sanjay Patel
20d1d5e75f [LibCallSimplifier] use instruction-level fast-math-flags for tan/atan transform
llvm-svn: 256964
2016-01-06 19:23:35 +00:00
David Majnemer
6385f16575 [SimplifyLibCalls] Teach SimplifyLibCalls about operand bundles
If we replace one call-site with another, be sure to move over any
operand bundles that lingered on the old call-site.

This fixes PR26036.

llvm-svn: 256912
2016-01-06 05:01:34 +00:00
Sanjay Patel
58be7e2c7d A (B + C) = A B + A C ; NFCI
llvm-svn: 256884
2016-01-06 00:32:15 +00:00
Sanjay Patel
2273c0c2a2 [LibCallSimplfier] use instruction-level fast-math-flags for fmin/fmax transforms
llvm-svn: 256871
2016-01-05 20:46:19 +00:00
Sanjay Patel
2d3c7242d3 [LibCallSimplifier] propagate FMF when shrinking binary calls
llvm-svn: 256682
2015-12-31 23:40:59 +00:00
Sanjay Patel
9333af147c [LibCallSimplifier] propagate FMF when shrinking unary calls
llvm-svn: 256679
2015-12-31 21:52:31 +00:00
Sanjay Patel
b1931a6a0c Variable names start with an upper case letter; NFC
llvm-svn: 256676
2015-12-31 16:16:58 +00:00
Sanjay Patel
4efb700a44 fix formatting; NFC
llvm-svn: 256675
2015-12-31 16:10:49 +00:00
Sanjay Patel
8312ed978c getParent() ^ 3 == getModule() ; NFCI
llvm-svn: 255511
2015-12-14 17:24:23 +00:00
Weiming Zhao
84bd343622 [SimplifyLibCalls] Optimization for pow(x, n) where n is some constant
Summary:
    In order to avoid calling pow function we generate repeated fmul when n is a
    positive or negative whole number.
    
    For each exponent we pre-compute Addition Chains in order to minimize the no.
    of fmuls.
    Refer: http://wwwhomes.uni-bielefeld.de/achim/addition_chain.html
    
    We pre-compute addition chains for exponents upto 32 (which results in a max of
    7 fmuls).

    For eg:
    4 = 2+2
    5 = 2+3
    6 = 3+3 and so on
    
    Hence,
    pow(x, 4.0) ==> y = fmul x, x
                    x = fmul y, y
                    ret x

    For negative exponents, we simply compute the reciprocal of the final result.
    
    Note: This transformation is only enabled under fast-math.
    
    Patch by Mandeep Singh Grang <mgrang@codeaurora.org>

Reviewers: weimingz, majnemer, escha, davide, scanon, joerg

Subscribers: probinson, escha, llvm-commits

Differential Revision: http://reviews.llvm.org/D13994

llvm-svn: 254776
2015-12-04 22:00:47 +00:00
Davide Italiano
0f427b7147 [SimplifyLibCalls] Transform log(exp2(y)) to y*log(2) under fast-math.
llvm-svn: 254317
2015-11-30 19:36:35 +00:00
Davide Italiano
ae7cdf685f [SimplifyLibCalls] Don't crash if the function doesn't have a name.
llvm-svn: 254265
2015-11-29 21:58:56 +00:00
Davide Italiano
75c47db0da [SimplifyLibCalls] Cross out implemented transformations.
llvm-svn: 254264
2015-11-29 21:00:43 +00:00
Davide Italiano
85963c8ad6 [SimplifyLibCalls] Tranform log(pow(x, y)) -> y*log(x).
This one is enabled only under -ffast-math. There are cases where the
difference between the value computed and the correct value is huge
even for ffast-math, e.g. as Steven pointed out:

x = -1, y = -4
log(pow(-1), 4) = 0
4*log(-1) = NaN

I checked what GCC does and apparently they do the same optimization
(which result in the dramatic difference). Future work might try to
make this (slightly) less worse.

Differential Revision:	http://reviews.llvm.org/D14400

llvm-svn: 254263
2015-11-29 20:58:04 +00:00
Davide Italiano
b0e9d52803 [SimplifyLibCalls] Use any_of(). Suggested by David Blaikie!
llvm-svn: 254239
2015-11-28 22:27:48 +00:00
Benjamin Kramer
cfb0838f67 [SimplifyLibCalls] Fix inverted condition that lead to an uninitialized memory read below.
Found by msan!

llvm-svn: 254238
2015-11-28 21:43:12 +00:00
Davide Italiano
916150a366 [SimplifyLibCalls] Use range-based loop. NFC.
llvm-svn: 254193
2015-11-27 08:05:40 +00:00
Benjamin Kramer
a5c875d940 [SimplifyLibCalls] Don't depend on a called function having a name, it might be an indirect call.
Fixes the crasher in PR25651 and related crashers using the same pattern.

llvm-svn: 254145
2015-11-26 09:51:17 +00:00
Weiming Zhao
2d64bb7e78 [Utils] Put includes in correct order. NFC.
Summary:
    Followed the guidelines in:
    http://llvm.org/docs/CodingStandards.html#include-style
    
    However, I noticed that uppercase named headers come before lowercase ones
    throughout the codebase. So kept them as is.
    
    Patch by Mandeep Singh Grang <mgrang@codeaurora.org>

Reviewers: majnemer, davide, jmolloy, atrick

Subscribers: sanjoy

Differential Revision: http://reviews.llvm.org/D14939

llvm-svn: 254005
2015-11-24 18:57:06 +00:00
Weiming Zhao
81cd3bf347 [SimplifyLibCalls] Removed some TODOs which are already implemented. NFC.
Summary:
D14302 implements tan(atan(x)) -> x
D14045 implements pow(exp(x), y) -> exp(x*y)

Patch by Mandeep Singh Grang <mgrang@codeaurora.org>

Reviewers: majnemer, davide

Differential Revision: http://reviews.llvm.org/D14882

llvm-svn: 253768
2015-11-21 06:10:20 +00:00
Pete Cooper
b753649d63 Revert "Change memcpy/memset/memmove to have dest and source alignments."
This reverts commit r253511.

This likely broke the bots in
http://lab.llvm.org:8011/builders/clang-ppc64-elf-linux2/builds/20202
http://bb.pgr.jp/builders/clang-3stage-i686-linux/builds/3787

llvm-svn: 253543
2015-11-19 05:56:52 +00:00